A long-delayed €350 million project to link the electricity grids of the Republic of Ireland and Northern Ireland is once again facing legal hurdles, as a group of farmers and landowners in Armagh and Tyrone mount a judicial review against its construction.
The North-South Interconnector, a 138km overhead line featuring more than 400 pylons—over 300 in the Republic and more than 100 north of the border—is designed to enhance electricity supply and lower costs across the island. However, the project continues to meet stiff resistance from local communities, particularly over its reliance on overhead infrastructure.
Safe Electricity Armagh and Tyrone (SEAT), the group leading the latest legal challenge, represents around 150 landowners and claims to reflect the views of 6,500 residents along the proposed 34km stretch of the interconnector in Northern Ireland. Planning permission for the northern section was granted in 2020 by Stormont’s Department for Infrastructure, following approval for the southern section in 2016 by An Bord Pleanála.
Opponents argue that the project will have a detrimental impact on the environment, agriculture, and tourism, while also posing health concerns for residents living near the high-voltage lines. SEAT and others insist that the cables should be placed underground, citing modern technology and international best practices. However, project developers Eirgrid and SONI maintain that undergrounding the line is not feasible due to the distance and power requirements involved.
John Woods, a long-time campaigner against the interconnector, has accused the Republic of using Northern Ireland as a “land bridge” to transmit electricity from Scotland to power energy-intensive facilities like data centres. “They need the power in the south, not here,” he said. “Northern Ireland is being treated unfairly, and this project is being imposed on our farmers and communities.”
Construction of a major substation in County Tyrone began three months ago, even as the legal case proceeds. Stormont has pledged to restore the site to its original state should the courts rule against the project.
Meanwhile, political controversy continues to swirl. Sinn Féin, which strongly opposes the use of pylons in the Republic, has faced criticism for backing the project in the North through its control of the Department for Infrastructure. Party TD Darren O’Rourke defended Sinn Féin’s stance, insisting that the interconnector should be delivered—but only if built underground. “That is the only way this project will gain community support,” he said.
In contrast, the System Operator for Northern Ireland (SONI) stressed the interconnector’s importance for meeting renewable energy targets and reducing grid constraints. “It is critical for future economic growth and the efficient operation of the Single Electricity Market,” a spokesperson said.
The planning permission is set to expire this autumn, meaning a successful legal challenge could delay the interconnector for several more years.